[PATCH AUTOSEL 6.1 45/57] net: wwan: t7xx: Ensure init is completed before system sleep

Sasha Levin
2023-05-25T18:44:07Z

From: Kai-Heng Feng <kai.heng.feng@canonical.com>

[ Upstream commit ab87603b251134441a67385ecc9d3371be17b7a7 ]

When the system attempts to sleep while mtk_t7xx is not ready, the driver
cannot put the device to sleep:
[ 12.472918] mtk_t7xx 0000:57:00.0: [PM] Exiting suspend, modem in invalid state
[ 12.472936] mtk_t7xx 0000:57:00.0: PM: pci_pm_suspend(): t7xx_pci_pm_suspend+0x0/0x20 [mtk_t7xx] returns -14
[ 12.473678] mtk_t7xx 0000:57:00.0: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x1b0 returns -14
[ 12.473711] mtk_t7xx 0000:57:00.0: PM: failed to suspend async: error -14
[ 12.764776] PM: Some devices failed to suspend, or early wake event detected

Mediatek confirmed the device can take a rather long time to complete
its initialization, so wait for up to 20 seconds until init is done.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wwan/t7xx/t7xx_pci.c | 18 ++++++++++++++++++
drivers/net/wwan/t7xx/t7xx_pci.h | 1 +
2 files changed, 19 insertions(+)

diff --git a/drivers/net/wwan/t7xx/t7xx_pci.c b/drivers/net/wwan/t7xx/t7xx_pci.c
index 226fc1703e90f..91256e005b846 100644
--- a/drivers/net/wwan/t7xx/t7xx_pci.c
+++ b/drivers/net/wwan/t7xx/t7xx_pci.c
@@ -45,6 +45,7 @@
#define T7XX_PCI_IREG_BASE 0
#define T7XX_PCI_EREG_BASE 2

+#define T7XX_INIT_TIMEOUT 20
#define PM_SLEEP_DIS_TIMEOUT_MS 20
#define PM_ACK_TIMEOUT_MS 1500
#define PM_AUTOSUSPEND_MS 20000
@@ -96,6 +97,7 @@ static int t7xx_pci_pm_init(struct t7xx_pci_dev *t7xx_dev)
spin_lock_init(&t7xx_dev->md_pm_lock);
init_completion(&t7xx_dev->sleep_lock_acquire);
init_completion(&t7xx_dev->pm_sr_ack);
+ init_completion(&t7xx_dev->init_done);
atomic_set(&t7xx_dev->md_pm_state, MTK_PM_INIT);

device_init_wakeup(&pdev->dev, true);
@@ -124,6 +126,7 @@ void t7xx_pci_pm_init_late(struct t7xx_pci_dev *t7xx_dev)
pm_runtime_mark_last_busy(&t7xx_dev->pdev->dev);
pm_runtime_allow(&t7xx_dev->pdev->dev);
pm_runtime_put_noidle(&t7xx_dev->pdev->dev);
+ complete_all(&t7xx_dev->init_done);
}

static int t7xx_pci_pm_reinit(struct t7xx_pci_dev *t7xx_dev)
@@ -529,6 +532,20 @@ static void t7xx_pci_shutdown(struct pci_dev *pdev)
__t7xx_pci_pm_suspend(pdev);
}

+static int t7xx_pci_pm_prepare(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct t7xx_pci_dev *t7xx_dev;
+
+ t7xx_dev = pci_get_drvdata(pdev);
+ if (!wait_for_completion_timeout(&t7xx_dev->init_done, T7XX_INIT_TIMEOUT * HZ)) {
+ dev_warn(dev, "Not ready for system sleep.\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
static int t7xx_pci_pm_suspend(struct device *dev)
{
return __t7xx_pci_pm_suspend(to_pci_dev(dev));
@@ -555,6 +572,7 @@ static int t7xx_pci_pm_runtime_resume(struct device *dev)
}

static const struct dev_pm_ops t7xx_pci_pm_ops = {
+ .prepare = t7xx_pci_pm_prepare,
.suspend = t7xx_pci_pm_suspend,
.resume = t7xx_pci_pm_resume,
.resume_noirq = t7xx_pci_pm_resume_noirq,
diff --git a/drivers/net/wwan/t7xx/t7xx_pci.h b/drivers/net/wwan/t7xx/t7xx_pci.h
index 50b37056ce5a4..5dffe24ef37b4 100644
--- a/drivers/net/wwan/t7xx/t7xx_pci.h
+++ b/drivers/net/wwan/t7xx/t7xx_pci.h
@@ -69,6 +69,7 @@ struct t7xx_pci_dev {
struct t7xx_modem *md;
struct t7xx_ccmni_ctrl *ccmni_ctlb;
bool rgu_pci_irq_en;
+ struct completion init_done;

/* Low Power Items */
struct list_head md_pm_entities;
--
2.39.2